Thread: Marking functions as "Local" or "Global"

Consider that in a file named "priv.c", I have:

Code:

int multiply(int n, int m) { return n * m; }

And in another file named "pub.c", I have:

Code:

int multiply(int n, int m);

int square(int n) { return multiply(n, n); }

Then I go ahead and build a static library using:

cc -c priv.c pub.c
ar rcs libsquare.a priv.o pub.o

This library will contain definitions for both "square" and "multiply". I'm wondering how I might go about hiding the definition for "multiply" in "libsquare.a". Essentially, I'm looking for a way to categorise some functions as "local" and others as "global".

I kindly welcome all thoughts and suggestions.

In my library the local functions are called in multiple files, so it seems I can't declare them with internal linkage, lest the library were implemented by one gigantic file.

I'll go with that then. Thank you both for taking the time to respond.

I don't think I'd make a function int multiply(int n, int m). Simply use C's multiplication operator.

Originally Posted by grumpy

I suggest the same comment applies to the square() function.

Perhaps this is better?

Code:

#include <stdio.h>

#define MNAME dafilename
#define MCAT_(a,b) a##b
#define MCAT(a,b) MCAT_(a,b)
#define LOCALFUNC(fn) MCAT(MNAME, fn) 
#define CALLLOCALFUNC(fn) MCAT(MNAME, fn)

static int LOCALFUNC(multiply(int x, int y))
{
    return x * y;
}

int main (void)
{
    printf("5*5==%d\n", CALLLOCALFUNC(multiply(5, 5)));

    return 0;
}

The multiply and square functions are inconsequential to my post, Hodor. Any other two functions, with one implemented in terms of the other, could have sufficiently illustrated the same case.

Thanks, Salem. I assumed there had to be an option like that, but it seems I was looking for it in the wrong place.